Abstract: A probability function for heart rate is determined using collected and measured heart rate values. One or more heart rate probability values are selected. Thresholds for arrhythmia rate zones are determined from the probability function based on the selected probability values. Determining the rate zone thresholds may involve determining a threshold for a lower 15 rate limit and/or determining one or more tachyarrhythmia rate zone thresholds. The number of rate zones may also be determined based on the probability function.

Abstract: Methods and systems are directed to detecting atrial tachyarrhythmia. A plurality of A-A intervals is detected. The detected A-A intervals are selected and used to detect atrial tachyarrhythmia. Selecting A-A intervals may be based on determining that A-A intervals are qualified. Qualified A-A intervals may be determined if a duration of the particular A-A interval falls outside a predetermined duration range, for example. Qualified A-A intervals may also be determined based on events occurring between consecutively sensed atrial events of the particular A-A interval, and whether the duration of the particular A-A interval falls within the predetermined duration range, for example.

Abstract: Systems and methods of performing rhythm discrimination within a patient's body using sensed hemodynamic signals are disclosed. The method can include the steps of receiving an electrical activity signal from an electrode located within or near the heart, detecting an event of the heart based on the received electrical activity signal, sensing one or more mechanical measurements using a sensor located within the body, analyzing a mechanical activity signal received from the sensor, and confirming the type of event based on the mechanical and electrical activity signals. The sensor can comprise a single pressure sensor configured to sense both atrial and ventricular activity within the heart.

Abstract: Systems and methods provide for sensing of cardiac activity from a subcutaneous, non-intrathoracic location, and detecting a cardiac condition necessitating treatment in response to the sensed cardiac activity. One of a number of cardiac therapies may be selectively delivered to treat the detected cardiac condition, such cardiac therapies including at least a tachycardia therapy, a bradycardia therapy, and an asystole prevention therapy.

Abstract: Atrial fibrillation or flutter detector having impedance unit, with measurement input, connected to atrial electrode line having electrode for unipolar measurement of atrium impedance and implemented to generate atrial impedance signal obtained in unipolar manner so that impedance signal comprises multiple impedance values detected at different instants within particular atrial cycle for each atrial cycle, comprising atrial contraction and the following relaxation of the atrium, and having a signal input, via which ventricle signal is supplied to detector, which reflects instants of ventricular contractions in chronological assignment to impedance signal, the detector having an analysis unit, implemented to average multiple sequential impedance signal sections of unipolar atrial impedance signal, delimited by two sequential ventricular contractions with one another and determine maximum amplitude of averaged unipolar atrial impedance signal section, compare to comparison value, and if maximum amplitude of ave

Abstract: Systems and methods for detecting and measuring cardiac contractile function of a heart using an acceleration sensor unit inserted within the heart, such as within a vein of the cardiac wall are disclosed. The systems and methods involve detecting the occurrence of electrical events within the patient's heart by inserting and positioning an implantable lead having an electrode near a cardiac wall as well as detecting mechanical events within the patient's heart by then inserting and positioning a cardiac motion sensor unit through the inner lumen of the implantable lead. Furthermore, the systems and methods do not require dedicated leads and may be used with preexisting implantable leads.

Abstract: Various aspects of the present subject matter provide devices and methods to treat AV-conducted ventricular tachyarrhythmia (AVCVT). According to various embodiments of the method, an AVCVT is sensed, an IVC-LA fat pad is stimulated when the AVCVT is sensed to block AV conduction, and bradycardia support pacing is provided while the IVC-LA fat pad is stimulated. Other aspects and embodiments are provided herein.

Abstract: An implantable cardiac stimulation device selects an arrhythmia therapy based upon the time of day. The device comprises an arrhythmia detector that detects an accelerated arrhythmia of a heart, and a data circuit that maintains a time record of cardiac cycle lengths developed during detected accelerated arrhythmias. A therapy circuit provides a selected therapy to the heart based upon the maintained time record of cardiac cycle lengths and the time of day.

Abstract: A device and method is disclosed for improving tachyarrhythmia detection when the ventricles are resynchronized by delivering paces to both ventricles separated by a specified negative offset interval. Timing of escape intervals and tachyarrhythmia detection is based upon senses from one of the ventricles designated as a rate ventricle. Techniques are presented for preventing tachyarrhythmia detection from being compromised when the rate ventricle is paced after the other ventricle.

Abstract: A subcutaneous cardiac stimulation system verifies accelerated arrhythmia detection before delivering accelerated arrhythmia therapy to the heart. The stimulation system includes a verification circuit that verifies detection of the accelerated arrhythmia with each of first and second sense channels utilizing first and second electrode configurations. The therapy circuit delivers the stimulation therapy to the heart if the accelerated arrhythmia detection is verified with each of the first and second electrode configurations. The system also compensates for transient rate changes during the detection of the accelerated arrhythmia.

Abstract: An aspect of the present subject matter relates to a system for providing baroreflex stimulation. An embodiment of the system comprises an adverse event detector to sense an adverse event and provide a signal indicative of the adverse event, and a baroreflex stimulator. The stimulator includes a pulse generator to provide a baroreflex stimulation signal adapted to provide a baroreflex therapy, and a modulator to receive the signal indicative of the adverse event and modulate the baroreflex stimulation signal based on the signal indicative of the adverse event to change the baroreflex therapy from a first baroreflex therapy to a second baroreflex therapy. Other aspects are provided herein.

Abstract: A system and method of treating an adverse cardiac condition, such as cardiac arrhythmia or a non-arrhythmic event, involves producing, by use of a patient actuatable non-implanted activator, an activation signal in response to a patient sensing a perceived adverse cardiac condition. The method further involves confirming, by an implantable medical device provided within the patient, that the patient is experiencing an actual adverse cardiac condition. A perceivable initiating signal instructing the patient or a physician to commence with a drug delivery regimen to treat the actual cardiac adverse condition is generated by the non-implanted activator. In one approach, the implantable medical device operates in a safe mode of pacing during drug treatment of the actual adverse cardiac condition. In another approach, an appropriate pacing, cardioversion or defibrillation regimen is initiated to treat the actual adverse cardiac condition.

Abstract: A system and method are provided for controlling atrial anti-tachycardia pacing (ATP) delivery based on detection of ventricular pro-arrhythmia during or immediately after atrial ATP. Ventricular pro-arrhythmia is detected based on one or more criteria relating to pro-arrhythmic changes including, but not limited to, ventricular rate changes, R-wave morphology changes, and/or 1:1 or nearly 1:1 atrial-ventricular conduction patterns persisting at high ventricular rates. Upon detecting ventricular pro-arrhythmia, a current atrial ATP sequence is aborted. Atrial ATP therapies may subsequently be temporarily or permanently disabled.

Abstract: Certain embodiments of the present invention disclose an electrostimulator, in particular an atrial cardiac pacemaker, comprising electrode connections which are connected to a stimulation unit for the delivery of stimulation pulses by way of the electrode connections, and a stimulation control unit which is connected to the stimulation unit and adapted to trigger the delivery of stimulation pulses and to determine the strength of the stimulation pulses and for that purpose to deliver a stimulation control signal to the stimulation unit, and a detection unit which is connected to the stimulation control unit and at least indirectly to the electrode connections and adapted to evaluate electrical potentials at the electrode connections and to detect intrinsic (natural, spontaneous) events.

Abstract: A method for routine monitoring and quality assurance of field asymmetry of high energy circular radiation beam producing equipment. The quality assurance process of field symmetry for devices such as stereotactic radiosurgery (SRS) systems is simplified by directly measuring the integration of the half-beam profile. The method of the invention provides that the field symmetry is obtained by positioning the tip of an ion chamber, with a collecting length approximately half the diameter of the beam, at the central axis of the beam, and rotating the ion chamber at varying angular positions, acquiring and comparing readings at desired angular positions. Each pair of readings from positions 180 degrees opposed from each other, are plugged into the equation, Asymmetry=2(R1?R2)/(R1+R2) to compute asymmetry.

Abstract: An implantable cardiac device is provided for adaptive ventricular rate smoothing during atrial fibrillation (AF). When AF is detected, the operation of the device is switched to non-atrial synchronized pacing mode such as DDI, DDIR, VDI, VDIR, VVI, or VVIR. The ventricular escape interval (VEI) is beat-by-beat modulated around a physiological interval zone (PIZ), which is determined by the pre-arrhythmia ventricular rate or the output of rate responsive sensor. The VEI remains unchanged if the preceding ventricular event is sensed and its RR interval is within the PIZ. Otherwise, the VEI is decreased asymptotically toward a lower interval threshold if the preceding RR interval is longer than the upper limit of the PIZ, or the VEI is increased asymptotically toward an upper interval threshold if the preceding RR interval is shorter than the upper limit of the PIZ.

Abstract: An abnormally rapid ventricular cardiac rate that results from atrial fibrillation can be reduced by stimulating a vagal nerve of the heart. An apparatus for such stimulation includes a power transmitter that emits a radio frequency signal. A stimulator, implanted in a blood vessel adjacent the vagal nerve, has a pair of electrodes and an electrical circuit thereon. The electrical circuit receives the radio frequency signal and derives an electrical voltage from the energy of that signal. The electrical voltage is applied in the form of pulses to the pair of electrodes, thereby stimulating the vagal nerve. The pattern of that stimulating pulses can be varied in response to characteristics of the atrial fibrillation or the ventricular contractions.

Abstract: An implantable device for terminating ventricular tachycardia is disclosed. The device includes a processor configured to determine a first antitachycardia pulse routine of N pulses. In the routine the first N?1 pulses are separated by a first cycle length and the Nth pulse is separated by a second cycle length that is shorter than the first cycle length. The device also comprises a lead coupled to the processor. The lead comprises an electrode configured to sense a tachycardia and further configured, under control of the processor, to administer the antitachycardia pulse routine.

Abstract: In some embodiments, a method for operating a cardiac rhythm management device may include one or more of the following steps: (a) sensing atrial depolarizations through an implanted atrial electrode, (b) administering a sequential CRT pacing therapy in a sequential CRT pacing mode to a left and right ventricle of a heart of a patient via implanted ventricular electrodes in a sequential bi-ventricular fashion, (c) switching from the sequential CRT pacing mode to a simultaneous CRT pacing mode, (d) administering a simultaneous CRT pacing therapy in the simultaneous CRT pacing mode to the left and right ventricle in a simultaneous bi-ventricular fashion, (e) analyzing the sensed atrial depolarizations to detect the presence of an atrial arrhythmia, (f) analyzing the sensed atrial depolarizations while in the sequential CRT pacing mode to detect the presence of atrial arrhythmia, and (g) sensing ventricular depolarizations of the left and the right ventricle.

Abstract: A medical device for implantation on an epicardial surface of the heart. The device has a transmural member providing optimal electrode locations for various therapies. The hemodynamically optimal therapy is guided by sensed left ventricular pressure and electrical activity. The device may be used alone or with a companion implanted cardiac rhythm management device.

Abstract: An implantable cardiac stimulation device provides biventricular pacing and pacemaker mediated tachycardia (PMT) detection. The device includes a pulse generator that provides right ventricular and left ventricular pacing pulse pairs to a right ventricle and left ventricle of a heart in a biventricular pacing mode. A sensing circuit senses activations of an atrium of the heart and a pacemaker mediated tachycardia detector times a plurality of V-P intervals from first issued pacing pulses of each pacing pulse pair to sensed activations of the atrium. A limit circuit of the PMT detector sets V-P interval limits response to the plurality of timed V-P intervals and a compare circuit determines if a last timed V-P interval is within the V-P interval limits. The timed V-P intervals are preferably recorded in a histogram format.

Abstract: The invention provides a cardiac rhythm management system which includes a tachyarrhythmia detection and classification circuit programmed to detect and classify a tachyarrhythmia, a biologic therapy delivery device configured to deliver or regulate an expression cassette suitable for terminating or preventing atrial fibrillation (AF), and a control circuit coupled to the tachyarrhythmia detection and classification circuit and the biologic therapy delivery device. Also provided is an implantable medical device for use in a body having a cardiovascular system, which includes an implantable device body including at least a cardiovascular portion configured to be in the cardiovascular system, and an expression cassette incorporated into the cardiovascular portion of the implantable device body, the expression cassette selected to express a gene product that terminates or prevents AF. Further provided are methods which employ particular expression cassettes to prevent, inhibit or treat AF.

Abstract: A method and system for delivering anti-tachycardia pacing (ATP) is disclosed. During delivery of an ATP burst, an implantable cardiac rhythm management device is programmed to sense evoked responses and determine whether or not the ATP burst has entrained the heart by counting the number of successive pacing pulses achieving capture. This information may then be used by the device to adjust the manner in which the ATP therapy is delivered.

Abstract: A device and method is disclosed for improving tachyarrhythmia detection when the ventricles are resynchronized by delivering paces to both ventricles separated by a specified negative offset interval. Timing of escape intervals and tachyarrhythmia detection is based upon senses from one of the ventricles designated as a rate ventricle. Techniques are presented for preventing tachyarrhythmia detection from being compromised when the rate ventricle is paced after the other ventricle.

Abstract: Techniques are described for detecting tachyarrhythmia and also for preventing T-wave oversensing using a narrowband bradycardia filter in combination with a narrowband tachycardia filter. In some embodiments, a separate wideband filter is also exploited. In one illustrative example, ventricular tachycardia (VT) is detected by: detecting a preliminary indication of VT using signals filtered by the bradycardia filter and, in response, confirming the detection of VT using signals filtered by the tachycardia filter. That is, the bradycardia filter, traditionally used only to detect bradycardia, is additionally used to provide a preliminary indication of VT. The tachycardia filter is then activated to confirm the detection of VT before therapy is delivered. In this manner, the tachycardia filter need not run continuously, but is instead activated only when there is some indication of possible VT, and hence power is saved.

Abstract: A method and apparatus for delivering therapy to treat ventricular tachyarrhythmias is described. A ventricular tachyarrhythmia can be classified into tachycardia or fibrillation zones using a rate criterion so that the tachyarrhythmia can be treated with either anti-tachycardia pacing or shock therapy, respectively. Rate stability and morphology criteria are employed to determine if a tachyarrhythmia in the fibrillation zone is actually monomorphic ventricular tachycardia which can be treated with ATP.

Abstract: Methods of using a template having a template data set and template parameters to provide improved alignment of captured cardiac signal data to a stored template. More particularly, in an illustrative method, a captured cardiac signal is first configured using template parameters for a stored template. Then, once configured, the captured cardiac signal is then compared to the stored template. Other embodiments include implantable cardiac treatment devices including operational circuitry configured to perform the illustrative method. In a further embodiment, more than one stored templates may be used. Each template can have independently constructed parameters, such that a single captured cardiac signal may be configured using first parameters for comparison to a first template, and using second parameters for comparison to a second template.

Abstract: An exemplary method includes providing an overdrive pacing rate and, determining an incidence limit for incidence of intrinsic atrial activity events, as well as the incidence of intrinsic atrial activity events The exemplary, method further includes comparing the incidence of intrinsic atrial activity events to the incidence limit and, based at least on the comparing, deciding whether to adjust the overdrive pacing rate. According to this exemplary method, the incidence limit is optionally a function of overdrive pacing rate. Another exemplary method includes determining a dwell limit wherein the dwell limit is optionally a function of overdrive pacing rate. Other exemplary methods, devices, systems, etc., are also disclosed.

Abstract: An implantable medical device is provided that comprises a pulse generator that provides atrial and ventricular pacing pulses on demand. The pulse generator times delivery of the ventricular pacing pulses based on an AV pacing interval. The device also includes an AV hysteresis module that extends the AV interval from a base AV interval to an extended AV interval to promote intrinsic heart activity. A refractory module establishes a PVARP interval equal to base PVARP interval following at least one of the ventricular pacing pulses. The refractory module lengthens the PVARP interval by adding a PVARP extension to a base PVARP interval to provide an extended PVARP interval.

Abstract: Embodiments of the present invention provide apparatuses and methods to predict and/or prevent episodes of ventricular tachyarrhythmia (for example, ventricular tachycardia and/or ventricular fibrillation). A method is provided for predicting an episode of ventricular tachyarrhythmia by detection and analysis of multiple patterns of vagal fatigue during a period of time.

Abstract: The extended AV interval of an auto intrinsic conduction search of an implantable cardiac stimulation device has premature atrial contraction protection. A timer times a base AV interval and the extended AV interval. If the heart is paced with the extended AV interval and a premature atrial contraction is detected, the extended AV interval is maintained. Once a predetermined number of consecutive premature atrial contractions are detected, the extended AV interval is reset to the base AV interval.

Abstract: The cell viability in cell transplantation is improved so as to achieve sufficient repair of organ. There is provided a regeneration treatment apparatus comprising: a heart rate detector which detects a heart rate of a patient; a memory part which stores a heart rate prior to stimulation; stimulating electrodes which stimulate a vagus nerve that controls an organ having transplanted cells; and a control unit which controls an intensity of a stimulation signal to be output from the stimulating electrodes to the vagus nerve so that the heart rate of the patient detected by the heart rate detector is decreased by 5 to 20% as compared to the state prior to the stimulation.

Abstract: A method is presented to calculate the relative contribution of different tissues, or tissue mix, to at least one data element in a medical object data set, the medical object data set containing data elements, the data elements assigning data values to respective positions in a multi-dimensional geometrical space containing more than one tissue, by means by which parameters are calculated for the at least one data element, the parameters being dependent on the data value of the at least one data element and data values of surrounding data elements in the neighborhood of the at least one data element, the parameters being further compared to combinations of said parameters for data elements occurring in the region of boundaries between tissues.

Abstract: An indication of an actual or potential heart failure condition is computed. One example includes monitoring a first heart rate preceding a first onset of a first sinus tachyarrhythmia episode. Upon detecting the first sinus tachyarrhythmia episode, the indication is automatically provided using information about the first heart rate and how quickly the first onset occurs.

Abstract: An implantable medical device and associated method discriminate between ventricular tachycardia and supraventricular tachycardia. Cardiac signals are sensed for detecting ventricular intervals corresponding to a tachycardia. Electrical stimulation pulses are delivered to cardiac neural tissue and verified as being effective in exciting the cardiac neural tissue. If the ventricular intervals corresponding to the tachycardia are increased in response to delivering stimulation pulses to the cardiac neural tissue, the tachycardia is detected as a supraventricular tachycardia.

Abstract: A system including at least one implantable sensor circuit adapted to produce an electrical sensor signal related to one or more physiologic cardiovascular events of a subject, a therapy circuit configured to provide anti-tachycardia pacing (ATP) therapy, and a controller. The controller includes a tachyarrhythmia detection circuit and an efficacy circuit. The tachyarrhythmia detection circuit is configured to detect a tachyarrhythmia episode in the subject using the electrical sensor signal, and to determine whether the tachyarrhythmia episode is of a type that is treatable with ATP. The efficacy circuit is configured to estimate an efficacy of a currently configured ATP therapy for the subject, and the controller is configured to alter a delivery regimen of the currently configured ATP therapy when the estimated ATP therapy efficacy is deemed insufficient. Other systems and methods are described.

Abstract: Miniature heart-monitoring devices, such as defibrillators and cardioverters, are implanted in humans to detect and correct abnormal heart rhythms Microprocessors and stored instructions, or algorithms within these devices govern how they interpret and react to abnormal heart rhythms. Algorithms that are too simple lead to unnecessary shocking of the heart, while those that are too complex consume considerable battery power. Accordingly, the inventor devised a relatively simple yet accurate algorithm for determining appropriate therapy options. One version of the algorithm computes three statistics—a range statistic, a minimum interval statistic, and a dispersion index—from a set of depolarization intervals. A scalar interval dispersion assessment, based on the three statistics, is then compared to a threshold to identify a rhythm as a flutter or fibrillation.

Abstract: The above object is achieved in accordance with the present invention by a cardiac stimulation device for stimulating a heart having a first ventricle and a second ventricle. The device includes a first ventricle sensing circuit that is configured to communicate with a first ventricle sensing electrode suited to be positioned in or at the first ventricle, to enable the first ventricle sensing circuit to sense the first ventricle. The device also includes a second ventricle pacing circuit, configured to communicate with a second ventricle pacing electrode suited to be positioned in or at the second ventricle of the heart, to enable the second ventricle pacing circuit to pace the second ventricle. The device includes a control circuit that operates with time cycles corresponding to normal heart cycles.

Abstract: Described herein are methods and devices that utilize electrical neural stimulation for inhibiting cardiosympathetic activity in order to reduce the risk of sudden cardiac death. In one embodiment, one or more stimulating electrodes are disposed near the left stellate ganglion. An implantable pulse generator delivers neural stimulation to the electrodes in a manner that inhibits activity of the ganglionic tissue.

Abstract: An implantable subcutaneous cardiac device includes at least two subcutaneous electrodes adapted for placement external to a heart beneath the skin of a patient. The device further includes an arrhythmia detector that detects a sustained tachyarrhythmia of the heart and a pulse generator that delivers anti-tachycardia pacing pulses to the subcutaneous electrodes in response to detection of a sustained tachyarrhythmia. The pacing pulses preferably have waveforms devoid of any exponential voltage decay and include rounded or substantially constant portions to minimize pain.

Abstract: A cardiac assist device senses conditions of a heart and controls the generation of various electrical stimuli in response to sense conditions of the heart. The cardiac assist device generates a electrical pulse so as to defibrillate a fibrillated heart when the cardiac assist device determines from the sensed conditions a state of fibrillation. The cardiac assist device generates a chaos control electrical signal so as to bring a pre-fibrillated heart condition back into a normal beating condition when the cardiac assist device determines from the sensed conditions a pre-state of fibrillation. Lastly, the cardiac assist device generates an electrical enhancement signal that causes a threshold of pacing cells in the heart to be exceeded in response to a subthreshold stimulus when the cardiac assist device determines from the sensed conditions a subthreshold pacing signal.

Abstract: An implantable cardiac stimulation device prevents pacemaker mediated tachycardias during autocapture. The device includes a refractory circuit that establishes a lengthened post ventricular atrial refractory period (PVARP) in response to a lengthened AV interval. Such a lengthened AV interval may occur as a result of the provision of a back-up pacing pulse or fusion beat evaluation during autocapture.

Abstract: A system and method for providing pacing pulses after a cardioversion/defibrillation shock, where the pacing pulses have a pacing rate at an initial value. The pacing rate is decreased from the initial value until at least one intrinsic cardiac contraction is detected. In one embodiment, the pacing rate is decreased by a set amount after pacing a set number of cardiac cycles. Providing the set number of pacing pulses and decreasing the pacing rate by the set amount is then repeated until at least one intrinsic cardiac contraction is detected. An intrinsic cardiac rate is then determined from the at least one intrinsic cardiac contraction. The pacing rate is then increased and maintained to be above (i.e., greater than) the intrinsic cardiac rate.

Abstract: In various method embodiments, a supraventricular arrhythmia event is detected, and a supraventricular arrhythmia treatment, including neural stimulation to elicit a sympathetic response, is delivered in response to a detected supraventricular arrhythmia event. Some embodiments detect a precursor for a supraventricular arrhythmia episode, and deliver prophylactic neural stimulation to avoid the supraventricular arrhythmia event. Some embodiments detect a supraventricular arrhythmia episode, and deliver therapeutic neural stimulation for the supraventricular arrhythmia event.

Abstract: A method and apparatus to slow a heart rate with subthreshold electric stimulation of the SA node. Stimulation is applied at a specific time in the cardiac cycle and at a specific subthreshold level. To control the heart rate, the stimulating signal may be modified automatically based on physiologic feedbacks. Stimulation may be applied using an implantable pulse generator directly to the SA node of the heart.

Abstract: Various embodiments can reduce mode switching in response to inappropriate but anticipated signals, such as far field R-waves. Additionally, various embodiments can also increase the alert period for detection of true atrial tachyarrhythmias in dual chamber pacing systems. Further, various embodiments can reduce mode switching or tachyarrhythmia response to same chamber delayed signals. In addition, various embodiments can increase the alert period for detection of true tachyarrhythmias in multisite pacing systems arising from the chamber being stimulated or sensed while minimizing repeated detection and counting of the same native depolarization or evoked response to effectively preclude mislabeling and detection of a normal rhythm as a tachycardia.

Abstract: A cardiac medical device used for delivering anti-tachycardia pacing in both the atrial and ventricular regions in a simultaneous manner, while preventing potential of inducing atrial arrhythmia. The pacing pulses may be synchronized in a gradual manner so that simultaneous delivery of the pulses is ultimately achieved at reduced risk of inducing atria arrhythmia. The pacing pulses may also be synchronized immediately after a determination is made whether simultaneous pacing purses will be delivered in the vulnerable regions of the cardiac cycle.

Abstract: Improved methods and apparatus for providing optimal anti-tachycardia pacing (ATP) regimens in response to the return cycle length (RCL) exhibited by an exploratory ATP sequence initially applied upon detection of the tachycardia episode are disclosed. When a tachycardia episode is detected, an exploratory ATP sequence comprising a burst of pacing pulses is delivered, and an exploratory RCL is measured following delivery of the exploratory ATP sequence. A database of successful and unsuccessful ATP regimens associated with stored exploratory RCL values. The measured exploratory RCL and database are utilized to formulate an ATP regimen that is more likely than not to convert the tachycardia episode to NSR.

Abstract: A cardiac rhythm management system can be used to detect episode beats associated with cardiac events in a subject's body. These events may be monitored and depolarization morphology information can be derived for candidate arrhythmic beats in an arrhythmia episode. An arrhythmic beat morphology template may be formed from selecting at least one of the candidate arrhythmic beats based upon user's labeling according to specific morphologies of one or more candidate episodes. Methods of use are also presented.

Abstract: A method and apparatus for treating an arrhythmia is provided. The method includes the steps of: (a) sensing at least one electrical signal from the patient's heart; (b) calculating a frequency spectrum of each electrical signal; (c) calculating a center frequency for each frequency spectrum; and (d) selecting an electro-therapy for delivery to the patient's heart based on the center frequency. The electro-therapy can be a pre-programmed anti-tachycardia pacing (ATP) therapy, a shock therapy, or no therapy at all. The method is performed through the use of an implantable cardioverter defibrillator (ICD). Also provided is a method of determining the optimal location to deliver the electro-therapy.